Since the beginning of the written word, humans have been concerned not only with how their words sound, but also with how they look. Before the advent of print, calligraphy was a major art form. With print, the art of creating and using fonts has superseded calligraphy in importance.
A font is a set of shapes representing each character in an alphanumeric character set. Usually the character-font shapes of a given font, that is, the shapes of the different characters in that font, share certain characteristics, such as horizontal and vertical position of certain shape features, the general width of their vertical and horizontal strokes, and whether or not they are serifed, bold, or italic, so that the characters of a given font look appropriate together.
In the current age of computer generated documents and WYSIWYG user interfaces, the most commonly used type of fonts are software fonts. Software fonts define the character-font shapes of a font in a manner than enables a computer to generate such shapes on computer screens and computer generated print outs. Such pre-defined font descriptions describe character shapes in a specified form or language. Some font languages represent shapes as bitmap images which can be translated directly to the pixels on a video display or a laser printer. This has the advantage of being fast, but it has the disadvantage of requiring a different set of font descriptions for each different size. More recently there has been a trend toward the use of scaleable font languages. These languages define a character's shape in terms of the one or more outlines which define its shape. Since these font descriptions define a shape in terms of lines and curves and since that definition is made with a high resolution, they can be used to generate font images of virtually any desired size.
There are currently several major scaleable font languages. They include PostScript, developed by Adobe Systems Incorporated, of 1585 Charleston Road, Mountain View, Calif. 94039, TrueType, developed by Apple Computer, Inc., 20525 Mariani Avenue, Cupertino, Calif. 95014; Speedo, developed by Bitstream Inc., the assignee of this application; and Intellifont, developed by the AGFA division of Miles Inc, 90 Industrial Way, Wilmington, Mass. 01887. Each of these languages uses a different code or format to describe and represent shapes in different ways. For example, TrueType uses quadratic Bezier curves to define the shape of curve segments, whereas PostScript and Speedo use Cubic Bezier curves, and Intellifont uses circular arcs.
Today there are many thousands of software fonts. The ability to vary fonts has many advantages. It lets a user vary the size of his letters to pack text more densely when necessary and to allow text to be more easily read. Using different fonts also has the ability to visually distinguish different parts of the text. This makes texts easier to scan and use. In addition, some fonts are more visually pleasing than others, whereas some are easier to read. Different fonts appeal to different aesthetic senses. Some appear traditional, some modern, some art nouveau, some art deco, some hand written, some humorous, and some shocking. The ability to select from a wide variety of fonts greatly increases the ability to tune the aesthetic message of a document.
Given the artistic and aesthetic benefits of being able to use the right font for the right documents, it is important that creators of documents be able to easily select and purchase fonts that have the right look and size for a desired usage, and that vendors of such fonts be able to make the available to users with as little overhead as possible.